3861521 has 2 divisors, whose sum is σ = 3861522. Its totient is φ = 3861520.

The previous prime is 3861463. The next prime is 3861547. The reversal of 3861521 is 1251683.

3861521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (3861547) can be obtained adding 3861521 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3857296 + 4225 = 1964^2 + 65^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3861521 is a prime.

It is a super-2 number, since 2×3861521² = 29822688866882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3861551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1930760 + 1930761.

It is an arithmetic number, because the mean of its divisors is an integer number (1930761).

Almost surely, 2^3861521 is an apocalyptic number.

It is an amenable number.

3861521 is a deficient number, since it is larger than the sum of its proper divisors (1).

3861521 is an equidigital number, since it uses as much as digits as its factorization.

It is an anagram of its base 12 representation: 3861521 = (1362815)₁₂.

3861521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 26.

The square root of 3861521 is about 1965.0753166227. The cubic root of 3861521 is about 156.8867020365.

The spelling of 3861521 in words is "three million, eight hundred sixty-one thousand, five hundred twenty-one".